The present invention relates to a flexible container for lifting, transport and storage of bulk material. The container comprises integrated lifting loops, at least one filling opening, sidewalls and a bottom.
For transport and storage of bulk material there are known several different types of containers. Regarding containers having integrated lifting loops, reference is made to Norwegian Pat. Nos. 136.744, corresponding to U.S. Pat. No. 4,269,723, and 138.134, corresponding to U.S. Pat. Nos. 4,191,229 and 4,136,723. These containers can be made with two lifting loops. Each of them has a width corresponding to half of the container's circumference. The first U.S. patent describes a container having a single layer bottom. The latter two U.S. patents primarily are related to a bottom construction formed by joining in pairs equally wide bottom flaps which are direct extensions of the container's walls. In this way there can be formed a substantially square double bottom of two crossing bottom loops.
There also exist several types of flexible containers, having their lifting loops sewn onto the container. European patent application No. 1696 relates to such a container having four lifting loops fastened to each corner of a substantially square container, and having a filling opening which has about the same area as the container's bottom. The lifting loops are made from narrow strips folded to form loops having two parts going downward, and at least one of these parts has the same length as the height of the container. Because the container has a large inlet opening, it may be equipped with a top covering or lid having a smaller filling opening. This lid is sewn to the container's sidewalls all the way around its circumference. However, this container does not possess the advantages resulting from application of integrated lifting loops and a double bottom. Containers according to the previously mentioned Norwegian and U.S. patents have proved themselves to be well suited for transport and storage of free-flowing bulk material and they are used for several different purposes. An essential reason for this success has been the simple construction comprising integrated lifting loops. However, these containers also have their limitations, especially during loading into large containers or railroad cards. Further, their construction is not quite ideal for filling large articles like 50 kilo bags for further transport and storage in the flexible containers.